The present invention relates to fluid flow control devices for controlling the flow of a fluid through a line. The invention is particularly useful in liquid transfusion apparatus for controlling the flow of the transfusion fluid, and is therefore described below with respect to this application.
The flow of a transfusion fluid must frequently be precisely controlled, and a number of devices have been developed for this purpose. However, the known techniques are usually of complicated construction which is costly to produce or difficult to preset and monitor.
An object of the present invention is to provide a fluid flow control device having advantages in the above respects. A particular object of the invention is to provide a fluid flow control device useful in a liquid transfusion system which device is of very simple construction and very easy to use.